I’ve gotten a lot of folks coming here for the information on the actual song featured in the show.
All of the details are available here, at the song-arranger’s site.
The portion of the show with the full song can be seen & heard here.
According to Bear McCreary, they will be releasing a Galactica soundtrack album in August to coincide with the Direct-to-DVD movie. That soundtrack will feature their version of the Bob Dylan song ‘All Along The Watchtower’.